Smartphone maker BlackBerry has published an open letter to customers in a bid
to reassure them of their future during "challenging times".

The open letter, published across social media and major media outlets today, tells customers: "These are no doubt challenging times for us and we don’t underestimate the situation or ignore the challenges we are facing.

"We are making the difficult changes necessary to strengthen BlackBerry. One thing we will never change is our commitment to those of you who helped build BlackBerry into the most trusted tool for the world’s business professional."

The letter comes days after after research firm Gartner recommended that customers should move to other technologies.

BlackBerry made a net loss of $965m (£600m) in its second quarter and has agreed a $4.7bn (£2.9bn) sale deal.

The Canadian firm has agreed in principle to be bought by a consortium led by Fairfax Financial, its biggest shareholder.

Its recent letter sets out measures to strengthen the company and restructure it with a goal to cut their expenses by 50 per cent.

It says: "We are bringing the most engaging mobile messaging platform to all, with our BBM launch for Android and iPhone. There are already around six million customers pre-registered to be notified of our roll out.

"This number is growing every day, and speaks to the tremendous opportunity we have to expand BBM beyond BlackBerry smartphones to make it the world’s largest mobile social network."

The company also write of its 'heritage of security' and its promise to continue evolving.

It says: "We changed with the market, embracing BYOD because we understand that as iOS and Android devices become common in the workplace, businesses still need to manage all of these different platforms seamlessly and securely.

BlackBerry has struggled this year as sales of its latest smartphones failed to match up growing competition from Apple and Samsung.

Slow sales of new models such as the Z10 led to a 45 per cent revenue decline last quarter and a $1bn loss.